title: A multidimensional investigation of children's /r/ productions: perceptual, ultrasound, and acoustic measures.
abstract: OBJECTIVE
  This study explored relationships among perceptual, ultrasound, and acoustic measurements of children's correct and misarticulated /r/ sounds. Longitudinal data documenting changes across these parameters were collected from 2 children who acquired /r/ over a period of intervention and were compared with data from children with typical speech.
  
  
  METHODS
  Participants were 3 children with typical speech, recorded once, and 2 children with /r/ misarticulation, recorded over 7-8 months. The following data from /r/ produced in nonwords were collected: perceptually rated accuracy, ultrasound measures of tongue shape, and F3 - F2 distance.
  
  
  RESULTS
  Regression models revealed significant associations among perceptual, ultrasound, and acoustic measures of /r/ accuracy. The inclusion of quantitative tongue-shape measurements improved the match between the ultrasound and perceptual/acoustic data. Perceptually incorrect /r/ productions were found to feature posteriorly located peaked tongue shapes. Of the children who were seen longitudinally, 1 developed a bunched /r/ and 1 demonstrated retroflexion. The children with typical speech also differed in their tongue shapes.
  
  
  CONCLUSIONS
  Results support the validity of using qualitative and quantitative ultrasound measures to characterize the accuracy of children's /r/ sounds. Clinically, findings suggest that it is important to encourage pharyngeal constriction while allowing children to find the /r/ tongue shape that best fits their individual vocal tract.
authors.affiliation: New York University, NY, USA. harriet.klein@nyu.edu
authors.forename: Harriet B
authors.initials: HB
authors.lastname: Klein
authors.forename: Tara
authors.initials: T
authors.lastname: McAllister Byun
authors.forename: Lisa
authors.initials: L
authors.lastname: Davidson
authors.forename: Maria I
authors.initials: MI
authors.lastname: Grigos
mesh_terms: D001184:Articulation Disorders / Q000000981:diagnostic imaging / Q000534:rehabilitation; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007805:Language Development Disorders / Q000000981:diagnostic imaging* / Q000534:rehabilitation; D008297:Male; D010700:Phonetics; D012044:Regression Analysis; D013061:Speech Acoustics; D013067:Speech Perception; D013068:Speech Production Measurement / Q000379:methods*; D013066:Speech-Language Pathology / Q000295:instrumentation / Q000379:methods*; D014059:Tongue / Q000000981:diagnostic imaging; D014463:Ultrasonography / Q000379:methods*
keywords: acoustics; articulation; speech production; speech sound disorders